Screening arrangements are widely used in the mining industry, particularly the coal mining industry, for the screening or classifying of ores and slurries. Material to be screened is passed over a vibratory screen deck. Apertures of screening panels arranged on the screen deck pass material having dimensions smaller than the apertures of the screen panels while materials having dimensions larger than those of the screening apertures are retained on a top surface of, and traverse, the panels of the screen deck for further processing.
Particularly with very fine apertures, the rigidity of the screening panel must be retained so that the apertures do not distort and pass materials larger than the aperture size. However, with these fine apertures, there is a danger of the apertures becoming blocked or blinding so that material which should pass through the apertures instead traverses the screen deck.
There is therefore a compromise between the need for a rigid panel and the need to inhibit blinding of the apertures.